Investigating the role of Sumagic growth retarder on vegetative growth and flowering of two narcissus genotypes

It is important to reduce the height of ornamental plants in order to produce short plants. One of the height control methods is the use of growth inhibitors. In order to investigate the effect of sumagic (uniconazole) on the growth and biochemical characteristics of daffodil, a factorial experiment was conducted in a completely randomized design with three replications. The first factor was sumagic (5 and 10 mg L-1, as foliar spraying and bulb immersion application), and the second factor was two genotypes of narcissus native to Iran (Shahla Shomal and Porpar Shomal). According to the results of the experiment, the highest number of flowers was obtained in the Porpar genotype and in the treatment of sumagic 5 and 10 mg L-1. The height of the flowering stem was the lowest in the treatment of sumagic 10 mg L-1 in immersion application, which showed a decrease of 37.64% compared to the control. Also, the lowest leaf length and the highest root length were observed in the treatment of sumagic 10 mg L-1 in immersion application. The highest amount of chlorophyll was obtained in the treatment of 5 mg L-1 sumagic immersion, and the highest amount of carotenoid was obtained in the Porpar genotype with 10 mg L-1 foliage spraying. The phenol content was at the maximum in the control and was not significantly different from the 10 mg L-1 sumagic. The highest percentage of nitrogen was obtained in sumagic at 10 mg L-1 immersion. The highest percentage of phosphorus was obtained with the application of 5 mg L-1 sumagic. The results of the present study showed that the use of sumagic can reduce the height of the daffodil plant and improve its physiological and biochemical characteristics.